ArsenalBio joins next-gen cell therapy field with $85M A round

ArsenalBio has exited stealth with $85 million to discover and develop cell therapies. The biotech aims to differentiate itself from the ever-growing pack of cell therapy startups with technology that enables the insertion of large DNA sequences without the use of viral vectors. 

The design and production of first-generation T-cell therapies entails using a viral vector to insert one cell-targeting transgene. ArsenalBio wants to use CRISPR-based genome engineering to rewrite far larger sections of DNA, potentially leading to better treatments that are faster and simpler to design and manufacture.

Some big names have bought into ArsenalBio’s idea. Beth Seidenberg’s Westlake Village BioPartners, the Parker Institute for Cancer Immunotherapy (PICI) and Kleiner Perkins participated in the round.

Responsibility for overseeing the use of the $85 million will fall on Ken Drazan, the former president of Grail. Drazen, CEO of ArsenalBio, is joined on the management team by Jane Grogan, Michael Kalos and Tarjei Mikkelsen. Grogan, Kalos and Mikkelsen used to work at Genentech, Johnson & Johnson and 10x Genomics, respectively.

The management team will build on the work of ArsenalBio’s scientific founders, who were brought into each other’s orbits through Sean Parker’s PICI. Broad Institute’s Bradley Bernstein, Kole Roybal from the University of California, San Fransisco (UCSF), the University of Pennsylvania's John Wherry and Nicholas Haining, formerly of Dana-Farber Cancer Institute, are among the scientific founders. 

Alexander Marson and Theodore Roth, both of UCSF, are the other two scientific founders. Marson and Roth were part of a large group that authored a Nature paper last year on the reprogramming of human T-cell function and specificity with nonviral genome targeting. 

The paper describes the use of an approach in line with that sketched out by ArsenalBio. Marson, Roth and their collaborators used a CRISPR-Cas9 targeting system to insert a 1.5-kb DNA cassette encoding for a TCR beta chain into a specific part of the T-cell genome. The researchers, who also used the approach to correct a pathogenic autoimmune mutation, see multiple benefits.

“In approximately one week, novel gRNAs and DNA repair templates can be designed, synthesized, and the DNA integrated into primary human T cells that remain viable, expandable, and functional. The whole process and all required materials can be easily adapted to good manufacturing practices for clinical use. Avoiding the use of viral vectors will accelerate research and clinical applications, reduce the cost of genome targeting, and potentially improve safety,” the researchers wrote. 

ArsenalBio will initially focus on applying its CRISPR-based genome engineering technology to cancer indications, but its longer-term vision is to develop immune cell therapies more broadly.